In a method and system for detecting digital image compositing, a first
artifact is detected in an uncompressed digital image. The first artifact
is characteristic of an earlier compression of the digital image with a
predetermined compression algorithm. An interpolation marker in the image
is evaluated to provide interpolation results. During the evaluating, a
second artifact of the compression algorithm is counteracted. The image
is classified responsive to the interpolation results. The first artifact
can be a blocking artifact and the second artifact and interpolation
marker can be different periodicities in the image.